Thank you for your reply. simonsaith wrote Checked the catalog, seeing that the 3D color LUT took up the majority of the size of the new catalog. The catalog stores a total of 1021 entries of custom 3D LUT (not from Adobe), presumably coming from some custom camera profiles/presets. Lightroom caches unique 3D LUT both in the catalog and on the disk to facilitate transportation of catalogs among different machines and quick access to them at develop time. Lightroom does not keep a copy of the 3D LUT at each history step. The catalog size increase for a newly created/exported catalog is a manifestation of this. It was introduced as part of the Lightroom Classic 7.3. Given that a reference to a 3D LUT could be buried in one of a history step (customer can go back in the history step to reference a 3D LUT at any time). Lightroom catalog does not currently have an infrastructure to do proper reference counting of custom 3D LUT usage. So it just includes a copy of every custom 3D LUT ever used. We have to consider this case of multiple catalog usage scenario and see if we can optimize it. Thanks for the report. P.S. The 3D LUT is also cached locally on disk at "~/Library/Application Support/Adobe/CameraRaw/Tables" on macOS. There is a similar Window directory location. I checked the directory you mentioned (TABLES) and I found 1021 files I think which totalled up to 172 MBs which is also close to the resulting catalog size. So its definitely relating to that. Also, whats interesting is, even after deletion of these files, they're automatically created again in a second after any new catalog is created or opened on an already infected machine. I checked a non-infected machine and this directory for them, is totally empty. Deleting camera profiles hasn't worked either. I am trying various permutations and combinations to alleviate the issue as two of my main machines are infected and work on them isn't possible because of this. I usually export a lot of sub-catalogs to send to my editors, and they're all super heavy even though they have very less images in them.
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